The present invention relates to the field of angioplasty. In particular, the present invention is a method for forming a guide catheter with a deformable tip.
Angioplasty has gained wide acceptance in recent years as an efficient and effective method for treating various types of vascular diseases. In particular, angioplasty is widely used for opening stenosis in the coronary arteries, although it is also used for treatment of stenosis in other parts of the vascular system.
The most widely used form of angioplasty makes use of a guide catheter positioned within the vascular system of a patient. The distal end of the guide catheter is inserted into the femoral artery located in the groin of the patient and is pushed distally up through the vascular system until the distal end of the guide catheter is located in the ostium of the coronary artery. The proximal end of the guide catheter protrudes outside of the patient's body to provide an entryway for subsequent insertion of additional angioplasty devices. The additional angioplasty devices includes dilatation catheters such as non-over-the-wire and over-the-wire balloon catheters.
Methods for forming catheters having soft, deformable tips are generally known. U.S. Pat. No. 4,551,292 to Fletcher et al. discloses one such method. Catheter stock is first ground down to form a frusto conical end portion. Next, the tapered end of the catheter stock is inserted into a suitable mold and a plastic, that is softer than catheter stock, is added to the mold to create a softer end portion on the catheter stock. The end portion of the catheter is then ground away and a forming tool is used to form a bulbous end on the end portion of the catheter. The resulting connection exhibits very little surface area contact between the catheter stock and the end portion.
It is evident that there is a continuing need for improved methods for forming guide catheters with deformable tips. Specifically, a method for forming a guide catheter with a deformable tip is needed that creates a lap joint tip bond exhibiting a large amount of surface area contact between the mating proximal end of the soft, deformable tip and the mating distal end of the main tubular member that makes up the guide catheter.